What replaced OTCBB?

Can you please elaborate on the successor to the OTCBB, the Over-the-Counter Bulletin Board? I'm curious to know what platform or system has taken its place in terms of facilitating the trading of over-the-counter securities. I understand that the OTCBB was a popular venue for trading penny stocks and other low-priced securities, but with its eventual demise, I'm interested in learning about the new avenues that investors have to explore for these types of assets. Additionally, I'd like to know if there are any notable differences or advantages between the OTCBB's successor and the original platform.